1. Field of the Invention
The present invention relates to an apparatus for attaching to a water heater and for use in conjunction therewith, to restrict and/or impede entry of floor-level gases into the water heater. More particularly, the present invention relates to a safety apparatus for adding on to an existing water heater, or for incorporating into a new water heater, to force incoming air, for combustion, to enter at a level elevated above the floor. The apparatus according to the invention, when properly installed on a water heater, significantly reduces the likelihood that flammable fumes from a volatile liquid, if spilled near a water heater, will be ignited by flames inside of the water heater.
2. Description of the Background Art
Many different types of water heaters are known and commercially available. Some examples of known designs for water heaters can be found in the disclosures of U.S. Pat. Nos. 4,856,982, 4,867,106, 4,940,042, 5,199,385, and 5,636,598.
In the design of the water heater disclosed in U.S. Pat. No. 4,940,042 to Moore, Jr. et al., a specialized conduit assembly extends from a water heater body, through a building wall, and ends outside of a building which houses the water heater. The conduit assembly of the Moore, Jr. '042 reference contains separate passages for incoming combustion air and outgoing exhaust gases. The conduit assembly acts to completely separate both incoming combustion air, and outgoing exhaust gases, from ambient room air inside the building where the water heater is situated. In the design of this reference, the water heater combustion chamber is sealed off from ambient room air around the water heater, and any fresh intake air, coming in to the combustion chamber, must be routed in from outdoors.
Most conventional gas-fired water heaters have a combustion chamber located near the floor of a base portion or body thereof, and also have an air inlet located adjacent the combustion chamber and very near the floor, to provide a source of fresh air to the combustion chamber. This type of design is logical because of the natural effect of flame, and heat thereof, to rise upwardly, and a tank for holding water to be heated may be conveniently located above a burner located at the floor of the water heater. The air inlet is normally located near the combustion chamber burner for simplicity of construction, and this is a good overall design for normal circumstances.
However, in some circumstances, flammable fluids such as gasoline, dry cleaning fluids, kerosene or paint thinner may be used in a basement, back room or shop area where a gas-fired water heater is located. If any significant accumulation of fumes, from these types of flammable liquids, builds up in a room, the fumes generally tend to collect, and mostly remain near the floor of a room, rather than becoming dispersed evenly throughout the room from top to bottom. Such collection of fumes near the floor takes place because fumes of this type are generally heavier than air, and where such an accumulation occurs, this may create a fire hazard.
Sometimes, a person working in such an area may accidentally drop one or more rags, which contain a flammable liquid, on the floor near the combustion air intake of a water heater. Furthermore, while never done intentionally, it is also possible that a flammable fluid may be accidentally and inadvertently spilled on a floor of a room where a gas-fired water heater is located.
In the unfortunate event that either flammable rags are left near an air intake for a water heater, or that this type of spillage takes place, it is further possible that fumes from the flammable liquid, or even some of the flammable liquid itself, may find its way into the combustion chamber of a water heater having its combustion air inlet located at floor level. It is then conceivable that flame inside the water heater could ignite those flammable fumes, and such a flame could then propagate and spread outwardly from the water heater, following the flammable liquid or the fumes thereof, and could start rags, liquid fuel, or other items which are situated near the water heater, on fire. If left unchecked or unnoticed, this type of fire could spread and cause further damage.
It is further possible that a fire caused by this type of accident could cause extensive damage and loss of property, or could even lead to loss of life in a worst-case scenario.
Accordingly, a need exists in the art for a water heater design, or for a safety apparatus which may be added to an existing water heater, that will effectively restrict and/or impede incoming combustion air from entering at floor level, and instead, will route incoming ambient room air to the combustion chamber from an area above floor level.